- Psychosexual identity disorder 302.6
- Psychosis 298.9
- Psychotic (see also condition) 298.9
- Pterygium (eye) 372.40
- Ptilosis 374.55
- Ptomaine (poisoning) (see also Poisoning, food) 005.9
- Ptosis (adiposa) 374.30
- PTSD (Post-Traumatic Stress Disorder) 309.81
- Ptyalism 527.7
- Ptyalolithiasis 527.5
- Pubalgia 848.8
- Pubarche, precocious 259.1
- Pubertas praecox 259.1
- Puberty V21.1
- Puckering, macula 362.56
- Pudenda, pudendum - see condition
- Puente's disease (simple glandular cheilitis) 528.5
- Puerperal
- Pulled muscle - see Sprain, by site
- Pulmolithiasis 518.89
- Pulmonary - see condition
- Pulmonitis (unknown etiology) 486
